#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
#define fastio ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define INF 0x3f3f3f3f3f

int main() {

    fastio;

    ll test;
    cin >> test;

    for(ll t = 0; t < test; t++){

        ll n , b;
        string s;
        ll c = 0;
        map<string , pair<ll,ll> > m;

        cin >> n;
        for(ll i = 0; i < n; i++){
            cin >> s >> b;
            auto it = m.find(s);
            if(it == m.end()){
                if(b == 0) m.insert(make_pair(s , make_pair(1,0)));
                else m.insert(make_pair(s , make_pair(0,1)));
            }
            else{
                if(b == 0) it.second.first++;
                else it.second.second++;
            }
        }

        for(auto x : m) c += max(x.second.first , x.second.second);

        cout << c << "\n";
    }
    return 0;
}